srp3.js

class Comment {
  styles = {
    username: {
      fontWeight: 'bold',
      paddingRight: '10px',
    },
    comment: {
      color: '#444',
    },
  };

  render () {
    return (
      <li style={this.styles} onClick={this.handleClick.bind(this)}>
        <span class="username">{this.props.username}</span>
        <span class="comment">{this.props.comment}</span>
      </li>
    );
  };

  handleClick () {
    alert('clicked!');
  };
}